This invention relates to a winch handle with a release feature that permits the cable to wind off of the winch drum without the handle rotating during the entire time the drum is rotating. The particular embodiment disclosed for purposes of illustration in this application is of a curtain control system for animal enclosures such as poultry houses. However, the invention has application in any environment where automatic release of a winch would be desirable for either functional or safety reasons.
Animal enclosures of this type and prior art systems for controlling ventilation and preventing or reducing animal mortality during power interruptions and extremely warm weather are disclosed in applicant's prior U.S. Pat. Nos. 3,915,377, 4,113,175, 4,428,278, 4,986,469 and 5,325,813, among others. Systems such as shown in these prior patents have substantially reduced animal mortality and labor requirements for raising poultry in large, environmentally controlled enclosures.
The present invention improves on prior art hand winch designs by providing a winch handle that permits faster operation of the curtain drop mechanism in the event of a power failure or other event triggering operation of the curtain drop device. The invention also improves safety by eliminating rapid rotation of the winch handle upon release and thus preventing accidental injury that might otherwise result from someone standing too close to a rapidly spinning winch handle during a release.